15506773920 has 768 divisors, whose sum is σ = 62078607360. Its totient is φ = 3582259200.

The previous prime is 15506773853. The next prime is 15506773921. The reversal of 15506773920 is 2937760551.

15506773920 is a `hidden beast` number, since 1 + 550 + 6 + 7 + 7 + 3 + 92 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (15506773921) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 118372255 + ... + 118372385.

It is an arithmetic number, because the mean of its divisors is an integer number (80831520).

Almost surely, 2^15506773920 is an apocalyptic number.

15506773920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 15506773920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31039303680).

15506773920 is an abundant number, since it is smaller than the sum of its proper divisors (46571833440).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

15506773920 is a wasteful number, since it uses less digits than its factorization.

15506773920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 266 (or 252 counting only the distinct ones).

The product of its (nonzero) digits is 396900, while the sum is 45.

The spelling of 15506773920 in words is "fifteen billion, five hundred six million, seven hundred seventy-three thousand, nine hundred twenty".